Remote control system



June 1, 1948.

A. P. JACKEL REMOTE CONTROL SYSTEM Filed Oct. 18 1945 4 Sheets-Sheet 1 W w i 1% 0MP 0555' d w 1. 2 1 w: 5 9 F 19 B J B i IN VENTOR Jackal.

H16 ATTORNEY '4 Sheets-Sheet s A. P. JACKEL REMOTE CONTROL SYSTEM 252$ zaszzasmsgsl 4522 465723552 June 1, 1948.

Filed Oct. 18, 1945 INVENTOR APzhaPPJa'c'liel HIS ATTORNEY i 'atenied June I, 1948 2,442,503 REMOTE CONTROL SYSTEM Arthur P. Jackal, Penn Township, Allegheny County, Pa., assignor to The Union Switch & Slgnal Company, Swissvale, Pa., a corporation of Pennsylvania Application October 18, 1945, Serial No. 623,142

11 Claims. 1

My invention relates to remote control systems, and more particularly to centralized traffic control systems for railroads of the type in which the control office and one or more remote stations are connected by a pair of line wires, over which impulse code signals are transmitted to control the operation of traflic governing devices such as track switches and railway signals, and to indicate at the oflice the condition of such devices and to also indicate the presence of trains in the various track sections.

The system of the present invention is of the time code type employing codes of long and short elements which are transmitted over a single line circuit and is an improvement upon that disclosed in my prior application for Letters Patent of the United States, Serial No. 496,907, filed July 31, 1943, for Remote control systems, now Patent No. 2,411,375, issued November 19, 1946. 1

In systems of this character it has been found advantageous to assemble the components in the form of coding and storage units each containing a group of relays, as shown in my prior application. More specifically, a coding unit is provided at each field location for transmittin indication codes and for selectively receiving control codes, together with a station storage unit for each unit group of traflic controlling devices, such as a power operated track switch and the railway signals which govern traflic movements over the switch, while at the office an individual control panel for each unit group of controlled devices is provided, each including the control levers for the devices of its group and a unit group of storage relays, together with an office coding unit which is connected by a pair of line wires with the station coding units and which serves to establish communication selectively between each panel and the corresponding station storage unit for the transmission of control codes and the reception of indication codes. Furthermore, the system is arranged to transmit the codes originating in the various storage units and panels one at a time in a given order of code superiority when they are initiated at the same time or while the line circuit is in use.

i The present invention relates to modifications of the system of my prior application, the principal object of which is to facilitate the control of large interlocking plants on multiple track railroads where, due to the number of track switches involved, the clearing of a signal may require the transmission of a series of codes in 2 order to align track switches controlled by different storage units as required for the desired route.

0ne object of the invention is to insure that under these circumstances the code for clearing the signal will be the last of the series to be transmitted, regardless of the order of superiority of the different codes.

In the system of my prior application, each control code includes a series of seven function steps for controlling a plurality of devices by the same code. Generally, two steps are used for the control of a track switch to normal or reverse and three for the control of a related group of signals governing traflic movements in two directions, leaving two spare steps which may be used for the control of a second track switch or for other purposes.

A feature of the present invention is the provision in each panel containing both'switch and signal levers, of a contact device or starting button associated individually with the switch lever by means of which codes may be initiated which 7 have less than the'normal number of .function steps; The signal controls are assigned to the last three function steps and are not transmitted unless the code is initiated by the operation of the usual starting button for the panel, which in the present system, as' heretofore, is so located as to be readily associated with the signal lever.

It follows that the'signal control relays of any station storage units are not operable by a code for controlling the switch control relays of the same unit, which has been initiated by the'starting device'associated with aswitch'lever.

Another feature of my invention is the provision of an improved route circuit network at the officeincluding route relays controlled by the switch and signal levers and indication relays for preventing the clearing of a signal or a change in a, routeexcept under proper-traffic conditions as reflected by the indication codes received from the stations. In accordance with this feature each route is locked at the office by the transmission of a code for clearing a signal which governs trafiic-movements over such route, regardless of subsequent lever manipulation, until code indications are received from the field that conditions are such that it is proper tocancel the route. l c

Other objects, purposes and features of my invention will be pointed out as the description proceeds. j I shall describe one form of apparatus mbodying my invention, and shall then point out the novel features thereof in claims.

Referring to the accompanying drawings, Figs. 1A, 1B and 1C, taken together, illustrate in condensed form the oflice coding equipment employed in one form of centralized traffic control system embodying my invention. The apparatus of Figs. 1A and 113 comprises the office coding unit for generating and delivering codes to the line circuit, this being similar, except for certain modifications, to the coding unit shown in Figs. 1A and 1B of my prior application hereinbefore referred to. Fig. 1C shows thecontrol levers and the coding and storage relays for two office panels for governing the office coding unit of Figs. 1A and 1B for the control of a typical track layout. Fig. 2 shows the operators-track diagram mounted adjacent the control levers of Fig. 16, the diagram being a miniature representation of the typical track layout chosen to illustrate my invention. Fig. 3 shows the route circuit network for governing the transmission of codes for controlling the signals. Fig. 4 shows the circuits for the various indication lamps mounted on the track diagram or associated with the levers of the individual control panels.

Similar reference characters refer to similar parts in each f the views.

The present invention relates more particularly to the portion of the system which is located at the control office, and for that reason a detailed explanation of the apparatus at the field stations with which it is operatively associated is not needed for an understanding of my invention, and the portions of the system which are located at the field stations are not shown herein. The coding units at the field stations may be of any type suitable for operative association with the coding unit of Figs. 1A and 13 shown herein, suitable apparatus being shown in my prior application, Serial No. 496,907, hereinbefore referred to, and in my Letters Patent of the United States No. 2,381,499, issued August 7, 1945, for Selective receiver for remote control systems.

Referring now to Figs. 1A and 13 showing the office coding unit, these views are similar to the corresponding views of my prior application except for the addition, in Fig. 1A, of a repeating relay OTP for timing the operation of the transmitter relay OT, and of a stick relay OLBS associated with the group of timing relays controlled by the line relay OR. The office coding unit is connected in multiple with the coding units at the field stations to a pair of line wires Y and Z, Fig. 1A, over which the codes are transmitted by interrupting or varying the current supplied thereto by the line battery 80, in the manner shown in Letters Patent of the United States No. 2,303,875, issued December 1, 1942, to George W. Baughman et al. The coding unit is overned primarily by the line relay OR, which is of the stick polar type and in receiving indication codes its upper winding is energized periodically by impulses of alternately opposite polarity supplied thereto through an impulse transformer RT as the line current is varied by the operation of a transmitter relay at the station transmitting the code.

The line relay OR, controls a chain of counting relays OI to 08, Fig. 1B, which are operated one for operation a second time, on the 9th to 15th steps, respectively, and relay 015 for operation in place of relay 08 on the 16th step. This is the maximum number of impulses transmitted and the apparatus then restores itself to its normal at rest condition.

Each code comprises a series of relatively short or long steps, the first of which is relatively long in a control code, and relatively short in an indication code, thereby identifying the direction of transmission, and the 2nd to 8th steps are arranged in one of 35 possible combinations of three long and four short steps for the simultaneous selection of an individual office panel and station storage unit between which seven control or indication channels are established in accordance with the relative length of the 9th to 15th steps.

Each code is identified by a number such as 234 or 235 of which the digits correspond to the long steps used for station selection. The selection is effected by the energization of a series of selector relays over contacts d of the counting relays and wires 2l28, comprising an entry relay E, Fig. 1C, energized on the first step, a first selector relay such as the relay 2F energized on the step corresponding to the first digit of the code call, a group selector relay such as 23G controlled thereby energized on the step corresponding to the second digit of the code call, and an individual panel or station selector relay such as 234s or 235s selected by the energized group selector relay and energized on the final step of the code call, which relay energizes a repeater relay SP, Fig. 1B, in the coding unit to prepare a circuit for the chain repeat relay OCR.

In response to an indication code, in which the first step is short, relay OR energizes a pole changer relay PC and a repeater relay PCP, Fig. 1A, as explained in Patent No. 2,303,875, and relay PCP prepares a circuit whereby relay SP energizes a code delivery relay OCD, Fig. 1B. The long or short character of the 9th to 15th steps of an indication code are stored by a series of register relays 9 to IE, inclusive, Fig. 1B, energized over contacts e of the counting relays. Relay 0CD prepares a circuit including contact f of relay 016 and wire 56, whereby a delivery relay 234D or 235D of the selected panel is momentarily energized to complete circuits over wires 49-55 to transfer the stored indications to the indication relays such as relay INWP, etc., Fig. 10, of the selected panel, where they are stored until a new indication code is received.

In the event an indication code includes more than three long steps in the selecting group, due to a fault, relay OCD operates a lookout relay X, Fig. 1A, as in my prior application, to interrupt the transmission of the defective code.

Relay OR and the counting and selector relays are also operated as above described in the case of a control code, but in this case relay OR is operated locally by the energization of its lower winding over the front or back contact 6 of the transmitter relay OT as the line circuit is periodically opened and closed by contacts b and d of relay OT.

Relay OR also governs a series of slow release timing relays OLI, 0L2, OLP, OLB and OLBP which function like the similarly designated relays in Letters Patent of the United States No. 2,229,249, issued January 21, 1941, to Lloyd V. Lewis, for Remote control systems, except as modified by the addition of the stick relay OLBS. More particularly, relays OLI and 0L2 operate .the selector and register relays selectively in re- 5 sponse to the long steps of a code, and these relays together with relay OLP determine the lengths of the long steps in a transmitted code. Relays OLB and OLBP control various circuits which they open to restore the apparatus to normal at the end of a code, or in the event the code is interrupted, and serve to measure the relatively longer intervals which separate successive codes.

Normally the timing relays are all released, and when relay OR is reversed on the first step of a code, the closing of its right-hand contact I) energizes relays OLI and L2 over back contact b of relay OLBS and then relays OLP, OLB, OLBP and OLBS pick up successively. Relay OLBS deenergizes relay OLI by transferring its circuit to the left-hand contact I) of 'relay OR. Relay OLI is initially energized for a longer period than in the arangement of the patent, where it is deenergized by relay OLZ, with the result that its operation is more uniform under varying con ditions. In the event relay OR remains reversed, relays OLI, OLP, OLB and OLBP release in the order listed to disable the coding unit, but relay 0L2 remains energized and holds OLBS energized over a stick circuit including contacts a of relays 0L2 and OLBS. When relay OR remains steadily in its normal position, these relays release in the order 0L2, OLP, OLB, OLBP, OLBS and OLI. A back contact 0 of relay OLBS replaces a contact of relay OLI in the circuit including wire 8| over which relay OI is energized on the first step of a code.

Each control code is initiated by the energization of a starting relay such as the relay 234ST or 235ST, Fig. 10, which completes a connection over its front contact 0 from terminal B at the back contact h of the associated selector relay over wire 41 and back contacts I) of relays OLI and 0L2, the closing of which indicates that the line is free, to energize the master relay OM, and relay OM at its contact d completes a pulsing circuit for the transmitter relay OT extending over wire 68 and the back contacts g of the counting relays Ol, 03, O and O1 to terminal B at back contact g of relay OIG, which circuit as herein disclosed, includes back contact I) of the added relay OTP, bridged by a front contact a of relay OT. Relay OTP is energized over front contact 0 of relay OT and contact 1 of relay OM each time relay OT picks up, and at the same time, relay OR is reversed by relay OT to energize the counting relay Ol, 03, etc., to open the pulsing circuit, whereupon relay OT releases to terminate the step at a time which measures the duration of the short odd-numbered code step, as determined by the rectifier connected across the terminals of relay OT. When relay OT releases, it reverses relay OR. which operates the next counting relay O2, 04, etc., and releases relay 0!, 03, etc., and relay OT also releases relay OTP which is similarly timed by a rectifier so as to release to cause relay OT to be energized at a time which measures the duration of a short even-numbered code step, and since the lengths of all of the short steps are determined by the same pair of relays, they may be made of uniform length more readily than heretofore.

To generate the long first step of a control code, relay OT is held energized over a branch of the pulsing circuit including wire 68 until relays OLI and OLP release, which may be traced in Fig. 13 from wire 68 over back contact 6 of relay SP, contact e of relay OLI in parallel with contact I) of relay OLP, back contact at of relay SP, front contact c of relay OI to terminal B at contact 9 ofi'eIay'OZ. To generate the other o'dd nunibered steps," relay OT is held energized u'ntil'r'elays OLI and OLP'release, by connecting terminal B to wire 6| to complete astick circuit for relay OT including its front contact I). To generate the even-numbered steps, relay OTP is held energized until relays 0L2 and OLP release, by connecting terminal B to wire 62 to complete a stick circuit for relay OT including its front contact a. On each long step of the station code call, relay OT or OTP is held energized until the corresponding selector relay 2F, 23G, etc., is energized, the pick-up circuit for which includes one of the wires 2228, contact d of one of the counting relays 02-08, back contact b or d of relay 0CD, back'contact b or d of relay OCR,'wire 63 or .64, contact 11 of relay OLI or 0L2, Fig. 1A, and extends to terminal B at contact a of relay OLBP over contact at of relay OLP and wires 58 and 60, when the coding unit is in the transmitting condition. At this time the connection from terminal B over contact 0 of the starting relay 234ST or 235ST has been disconnected from wire 41 by the operationof relay E and extends over front contact g of relay E, or over corresponding contacts of relays 2F or 23G as these are operated, to one of the wires 32-38 and over contacts 0 of the counting relays to wires 6| or 62. On the function steps 9 to 15 of the control code, relay OT or OTP isheld energized until relay OLP releases by reason of a connection from wires 6| and 62 over front contacts e and of relay OCR, front contacts 1 of the counting relays and wires 39-46 which extend to terminal B over contacts of the control levers such as I SW or ZSG of the selected panel to terminal B at contacts e, f, g and h of the energized selector relay such as relay 234$.

The starting relay 234ST by which the code is initiated and the panel is selected is released by opening its stick circuit including wire 46 and extending to terminal B at back contact 1 of relay O8 and also at back contact g of relay OM, on the 8th step, and this relay is thereby placed in condition to be immediately reenergized to efiect the transmission of a second code from the same panel.

The wayside circuits by which the track switches and the railway signals are operated by the codes as well as those by which they are electrically interlocked and which have to do with the safety of operation in accordance with trafiic conditions may be arranged in any desired manner, but in order to conveniently illustrate my invention, the portions of the system comprising Figs. 2, 3 and 4 have been arranged as required for the control of a specific form of interlocking system, namely, that shown in an application. for Letters Patent of the United States, Serial No. 598,695, filed June 11, 1945, by Earl M. Allen, for Centralized traffic control systems for railways. This Allen system is characterized by the provision of a control board in which all of the lever lamps as well as those for illuminating the track diagram are normally dark, the manipulations involved in setting up routes being thereby facilitated because the only lamps lighted at any one time are those which are directly of interest to the operator.

Although the Allen system for this reason is suitable for the control of large layouts, I have, for simplicity, chosen a track plan to illustrate my invention, employing only two panels and two station storage units for its control. As shown by-the miniature diagramof Fig. 2," the track layout comprises a stretchermain trackincluding a single switch I and connected to a parallel main track by two cross overs 3 and 5. The switch levers ISW and SSW and the signal lever 2SG of one panel, to which is assigned the code number 234, control the track switches l and 3 and the opposing signals 2RA, 2RB and 2L, while the switch lever SSW and the signal lever 4SG of a second panel, numbered 235, control the switches 5 and the signals 4R and 4L.

The switch levers as shown hereinare of the push-turn type, such, for example, as shown in Letters Patent of the United States No. 2,289,- 736, issued July 14, 1942, to Clarence S. Snavely et al., having an auxiliary normally open contact p, which is closed momentarily as the lever is moved from one operative position to another, and when closed, energizes the starting relay with the same effect as when the panel starting button is operated. It follows that in the system of the present application, a control code may be initiated either by the momentary operation of the usual starting button for the panel, such as the push button ZSTB, as heretofore, or by the operation of the switch lever of the panel.

One advantage of this arrangement is that it becomes unnecessary to mount the switch levers in alignment with the starting buttons to insure that the proper button will be operated when a switch control is to be issued, but these levers may be located in alignment with the corresponding switches on the track diagram where they may more readily be identified with the track switches they control.

In order to avoid the possibility of transmitting signal controls improperly as the result of the operation of a switch lever, and to make it unnecessary for the operator to remember to which panels the various switch controls are assigned, the signal control steps 13, 14 and 15 are omitted from the codes initiated by switch lever operation, as already mentioned, so that the function steps of such codes comprise only the 9th to 12th steps, inclusive, and the signal control relays are not actuated. This is accomplished by a modification of the circuit for the counting relay 05, Fig. 1B, of the oifice. coding unit, so that in a control code initiated by switch lever operation this relay does not respond when relay OT is energized to begin the l3thstep, and relay OT which is energized at the time over wire 68 andback contact 9 of relay 05, remains energized to hold the line circuit open until relay OLBP releases, whereupon relays OM and OT release and relay OR i restored to normal, reenergizing the timing relays, and then releasing them in the normal order as at the end of a complete code.

By reference to Fig. 1A it will be seen that on each odd-numbered step the right-hand contact a of relay OR connects terminal B over front contact 27 of relay OLBP to wire l9, and in Fig. 13, during the first cycle of operation of the counting relays, relay O5 picks up over the connection from wire l9 including back contact g of relay OCR, back contact a of relay O3 and front contact b of relay 04. During the second cycle of operation, when back contact 9 of relay OCR is open, back contact h of relay OM provides a connection to wire [9 to pick up relay O5 in the case of an indication code, but not in the case of a control code initiated by switch lever operation, which code is terminated on the 14th step but without registering the character of the l3thstep in the station storage unit, due to the 8 release of relay OLBP and of a similar relay in the station storage unit on that step.

The transmission of a control code of 16 steps, including the signal control steps, is accomplished by the provision of an auxiliary starting relay such as the relay 2GST or 4GST, Fig. 1C, for each panel having a signal lever, and bythe provision of a control-relay GC, Fig. 1B, in the oflice coding unit. I

When a control code is initiated by the operation of the usual starting buttonsuch as the push button ZSTB, Fig. 1C, theauxiliary relay ZGST is energized along with relay 234ST over the contact 12 of button ZSTB, which is connected to terminal B at back contact I) of a relay RST, over wire 65. Relay ZGST is held energized over a stick circuit extending to terminal B at front contact b of relay 234ST, and when relay 234ST releases on the 8th step, a connection over wire 10 is made at back contact e of relay OIG, by which relay ZGST is released on the 16th step. With relay 2GST energized, the control relay GC is energized on the 12th step over the circuit from terminal B at front contact a of relay OM, Fig. 1A, wire 69,- front contacts d of relays 2348 and ZGST, Fig. 1C, wire 61, contact 9 of relay 04, contact 0 of relay OCR through relay GC to terminal C, and relay GC is held energized over a stick circuit including its front contact 41 extending over wire 50 to terminal B at contact a of relay OLBP. The closing of contact (1 of relay GC bridges the open contacts a of relay OCR and h of relay OM in the circuit from wire- 19 to relay 05, so that relay O5 responds on the 13th step and the counting relays operate through sixteen steps in the normal manner.

Each indication code also includes the full quota of sixteen steps as already pointed out, and in view of the similarity of the indication system to those of my prior application and of Patent No, 2,229,249, it is deemed sufiicient for an understanding of the present invention to merely identify the various indication relays by pointing out their functions and the conditions under which they are operated. It will be understood that indication codes are initiated automatically in response to changes in traffic conditions and also that each station storage unit initiates an indication code following its reception of a code from the ofiice which operates its selector relay corresponding to relay 234s.

The relays INWK and IRWK are normal and reverse switch relays, energized only when switch is in a corresponding normal or reverse position and in correspondence with its control relay governed by the switch lever ISW. Relays 3NWK and -3RWK, and relays ENWK and SRWK similarly indicate the condition of the crossover switches 3 and 5, and since the two switches of a crossover are operated in unison by a single control relay but one pair of indication relays is required for each crossover. Relays ITK and STK are track indication relays which are energized when the corresponding switch sections are occopied to light red lamps, such as lamp ITKE in the track diagram. ReIay'ZGK is a signal indication relay which is energized when the signals ZRA, ZRB and EL, controlled by lever ZSG, stand at stop, while relay 4GK similarly indicates the condition of the signals 4R and 4L, controlled by the signal lever GSG. Relays 2ASK and 4ASK are approach locking indication relays which are energized to indicate the release of approach locking relays associated with the signals governed-by levers ZSG and 45G respectively, ,by

means of which the track switches and signals are interlocked electrically, there being one approach locking relay for each direction for each signal or group of signals controlled by the same lever, such as the relays ZRAS and ZLAS shown in the above-mentioned Allen application and also in Letters Patent of the United States No. 2,343,784, issued March 7, 1944, to R. A. McCann et al. To permit the clearing of a signal, the associated approach locking relay must first be released, and this is efizected by the operation of the associated signal control relay in response to a control code for clearing the signal, as in the McCann et al. patent. When released, the approach locking relay prevents the operation of any track switch in a route governed by the associated signal, or the clearing of the opposing signal at the'opposite end of the route, and also prevents the storage of switch controls by rendering the control relays for these switches nonresponsive to switch control codes, as explained more fully in the application and patent referred to.

In order to prevent the release of the approach locking relays except when conditions are proper,

1 the transmission of control codes for clearing the signals is governed by a system of route relays such as the relays 2LGS and ZRGS there being one such relay at the ofilce for each approach locking relay in the field. These route relays are controlled over a route circuit network, Fig. 3, conforming to the track layout. Each route relay such as 2RGS is energized in response to the reversal of the associated signal lever ZSG only when a route governed by signal ZRA or ZRB is set up and indications thereof have been received at the office corresponding to the positions of the switch levers.

By reference to Fig. 3 it will be seen that when lever ZSG is operated to the right, for example, if the switch levers and switch indication relays occupy positions corresponding to any of the routes governed by signal ZRA or ZRB, a circuit will be closed from terminal B at back contact b of relay ZLGS or 4LGS to contact 12 of lever ZSG and thence over back contacts I) of relays ZGST and ZASK through relay 2RGS to terminal C, energizin relay ZRGS. In Fig. 4, contact of relay ZRGS connects terminal B to a circuit including other contacts of the energized switch indication relays, to light an exit lamp such as the lamp ZLX, located as shown in Fig. 2, at the exit end of the established route. This gives the operator an opportunity to verify the correctness of his selection of a route and indicates its destination without the necessity for checking the positions of each of the switch levers.

In response to the operation of the starting button 2STB to initiate the transmission of the code for clearing the signal, relays ZGST and ZMST become energized and contact b of relay 2GST operates to insert contact a of relay ZRGS into the route circuit over which relay ZRGS is energized, thereby insuring that the signal lever and starting button are operated in the proper sequence.

When the 12th step of this control code is reached, the energization of relay GC as already described completes a circuit from terminal B at its contact b over wire 48, contacts e of relay ZRGS and 234s, back contact f of relay 235D through relay ZASK to terminal C to energize relay ZASK, contact b of which disconnects relay ZRGS from the route circuit and holds it energized over a stick circuit including front contacts b of relays ZASK and ZRGS, thus anticipating the locking of the route in the field by the signal clearing code and the subsequent energization of relay ZASK by an indication code as a result thereof. The route relay such as 2RGS is held energized until an indication code is received which releases relay ZASK, indicating to the operator that he is free to establish a new route.

The control code which clears the signal 2RA or ZRB is characterized by a long 14th step, and by reference to Fig. 10 it will be seen that this step is made long by holding relay OTP energized over a circuit from terminal B at contact 9 of relay 2348, the right-hand contact a of lever ZSG, contact g of relay ZRGS, wire 44, and thence in Fig. 13 over contact 7 of relay 06, contacts e or relays 0L2 and OLP in parallel, front contact of relay OCR to wire 62, and in Fig. 1A, over contact a and'the winding of relay OTP to terminal C.

It will be seen that the 13th and 14th steps will be short steps regardless of the position of the signal lever and will be effective to hold the signals governed thereby at stop, unless the proper route relay is energized.

The present system also includes means for transmitting a recall code for the purpose of initiating an indication code and thereby verifying the condition of the station, but Without operation of any of the control relaysat the station, this being an improvement upon the recall apparatus of my prior application and involving the addition of a relay RST, Fig. 1B, for controlling the recall relay RCR.

The transmission of a recall code is effected by pressing a recall button RCB, Fig. 1B, and then operating one or more of the starting buttons to energize the starting relay such as 234ST for each recall code to be transmitted, after which button RCB may be released, relay RST being held energized over a stick circuit including wire 66 and extending to terminal B over contacts d of the starting relays until each of the recall codes is transmitted.

Relay RST energizes relay RCR as soon as the code is initiated over the circuit from terminal B at contact 9 of relay OM, wire 69, and contact 0 of relay RST. This serves to interrupt the circuit for energizing relay OI on the 9th step, which circuit as shown in Fig. 13 includes front contact 9 of relay OCR and back contact b of relay RCR, and relay OT therefore remains energized on the 9th step until relays OLBP and OM release to terminate the transmission, following which relay OR is restored to normal, reenergizing the timing relays and then releasing them in the normal order as at the end of a complete code. The recall code thus includes but 10 steps, and the character of the 9th step is not registered due to the release of the station storage unit on that step. This code is eifective, however, to initiate an indication code because this is effected by the operation of a selector relay corresponding to relay 234s, which relay is operated on the step prior to the 9th step.

One advantage of this arrangement is the provision of a recall indicator lamp ROE, Fig. 1B, which is dimly lighted through a resistor over a connection to wire 66 at back contact a ofrelay RST as long as a control code is stored for transmission, whereby the operator is enabled to delay the operation of the recall button until the stored controls are transmitted if he so desires. Lamp RCE is brightly lighted when relay RST is energized, due to the connection to terminal B at 11 front contact b of relay EST, to distinctively indicate the storage of recall codes.

Another advantage is that relay RST when energized disconnects terminal B from wire 65 over which the contacts 17 of the starting buttons are supplied with current, so that the relays GST are not operated, but each starting button serves only to operate the associated starting relay such as 23481, and any other functions which may be assigned to the starting buttons are temporarily suspended.

As already mentioned, the indication lamps shown in Fig. 4, are arranged to conform to the requirements of the normally dark control panel of the system of the Allen application hereinbefore referred to. Each switch lever is provided with a single red lamp such as lamp IWE mounted above the switch lever which becomes lighted when the lever is moved to a new position to initiate a switch control code and becomes dark again when an indication is received that the switch has assumed a corresponding position. Each signal lever'such as lever ZSG has a red lamp ZNE mounted above the lever which is controlled by the route relays ZRGS and ZLGS when the lever is reversed and also by the indication relays ZASK and ZGK controlled by the signals which the lever controls, so that the lamp ZNE becomes lighted from the time the signal lever is reversed until a signal clear indication is received, and also so long as the signal lever remainsreversed following the reception of a stop signal indication. Lamp 2NE also has a connection to one terminal FB of a source of interrupted current whereby it is caused to display a, flashing indicationin the event a signal is put manually to stop and relay ZASK remains energized due to locked conditions in the field, or if a'locking relay in the field releases due to a fault, when the signal lever is in its normal center position. When a signal clear indication is received, the red lamp such as 2NE is extinguished and a green lamp such as ZRAE or 2RBE becomes lighted at the signal location on the track diagram, in response to the energization of the signal indication relayv such as relay ZGK.

In order to inform the operator more fully of the operation of the coding apparatus I have provided a code indicator relay such as the relay 234CK, Fig. 4, for each panel, which relay i energized by the associated starting relay as soon as a code is stored for transmission and is main tained energized until the next indication code is received from the corresponding station storage unit to operate the delivery relay 234D. A code indicator lamp such as 234GB is brightly lighted over contact f of relay 234ST and front contact b of relay 2340K from the time a code-is stored for transmission until relay 234ST releases on the8th step of the code, and then is lighted dimly over a connection to terminal B through a resistor until the return indication is received from the corresponding station storage unit. This indication will of course persist as a warning to the operator in the event the codes are not properly transmitted or received. This lamp also indicates the reception of an indication code initiated automatically, in which case it is lighted for a brief period over the circuit including back contact I) of relay 234CD and contact 7' of relay 234s.

Having thus described the various components ofthe system of my invention, I shall now explain its mode of operation under different assumed conditions, starting with the apparatus in its normal condition as shown with all panel lamps dark and pointing out the operations involved in clearing signal ZRB for a train movement over the route extending to signal AL.

The operator will first reverse the switch levers [SW and 3SW and move the signal lever 25G to the right. The starting relay ZSL ST is energized by the momentary closing of the contacts p of the switch levers to initiate the transmission of a 14 step control code, provided the line is free, but relay ZRGS, Fig. 3, remains released because ter minal B has been disconnected from contact I) of lever ZSG by the reversal of contacts at of levers ISW and 38W. The operation of each switch lever causes the lighting of the associated red lamp such as IWE, and the reversal of the signal lever causes lamp ZNE to be lighted, and the code indicator lamp 234CE is also lighted, becoming dim when the code is issued. The responseof the switch control relays to this code initiates an indication code whereby relays INWK, 3NWK and 2340K are released, extinguishing the code'indicator lamp, and indicating the delivery of the control code even though the red lamps remain lighted. When switch I or crossover 3 completes its operation, a second indication is initiated, including indications of both if completed in time, otherwise two successive codes are transmitted, relays IRWK and ERWK becomingenergized to extinguish the switch lever lamps, and since lever ZSG is in its right-hand position, relay ZRGS becomes energized to light the exit lamp 4LX indicating the destination of the route on the track diagram.

The operator now presses button ZSTB energizing relays ZGST and 234ST to initiate the transmission of a 16 step control code to clear signal ZRB, relay ZASK becoming energized on the 12th step to hold relay ZRGS energized as already'described. Lamp 234CE becomes lighted to indicate the transmission of this code, and when the signal clears an indication code is received which includes elements for energizing relay ZGK and for holding relay ZASK energized, whereupon lamps 2340151 and 2NE are extinguished, and the-green lamp ZRBE at the signal location on the track diagram becomes lighted.

In the event signal 2RB is put to stop automatically by a train entering the route, an indication code is returned to energize relay ITK, lighting lamp 'ITKE, and to release relays ZGK and ZASK, extinguishing lamp ZRBE and lighting lamp ZNE until the operator restores lever ZSG to normal.

To put signal ZRB manually to stop, the operator restores lever 2SG to its normal center position and presses button ZSTB to initiate a 16 step control code in which the 14th step, controlled over wire 44, is short, due to the opening of the right-hand contact a of lever ZSG, in Fig. 10. Usually the reenergization of the locking relay by which relay ZASK is released will be delayed under this condition for a time, and in response to the release of relay ZGK, lamp ZNE will be caused to flash until a second indication code is received at the end of the time locking period to release relay 2ASK.

I shall now assume that lever 28G is moved to the right as in the above example, but that the starting button ZSTB is also operated. The control code will then contain 16 steps, due to the energization of relay 2GST. If either lever ISW or 3SW is reversed before the 12th step of the code is reached, relay ZRGS releases and by opening its contact 9, Fig. 10, in the connection to wire 44, causes the 14th step to be short so that the signal control relay is not operated to lock the route or to clear the signal, and the switch controls remain efi'ective as in the preceding example. On the other hand, the reversal of a switch lever after the 12th step is reached is devoid of efiect because the switch control steps have already been passed, and relay 2RGS is disconnected from the route circuit and held energized by relay ZASK. The starting relay is reenergized by the switch lever movement to initiate a second code having but 14 steps but this finds the switch control relays locked against operation as the result of the transmission of the preceding code, the effect of which was to clear the signal for the route established at the time of transmission of that code. The code which includes elements for controlling the signal is therefore transmitted but once, unless it is reinitiated intentionally. This is desirable because of the uncertainty which arises in the case of signals which are controlled by trafiic conditions as well as by code, as to whether the signal control element of a code transmitted at about the time a train is passing the signal should be one for holding it at clear or for holding it at stop.

Returning again to the example first given, assume that levers ISW, ZSG and 3SW have been operated to the right and that the exit lamp 4LX is lighted to indicate that the route is established but that the starting button has not been operated. The operator may now reverse the traffic direction if required, by restoring lever ZSG to normal and operating lever 4SG to the left, releasin relay ZRGS and energizing relay dLGS, whereby signal 4L may be cleared by operating the starting button AS'IB, relay 4ASK becoming energized in this instance to lock the route on the 12th step of the code.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In a remote control system provided with a transmitter relay having a regulated release period for supplying impulses to a line circuit, and having a chain of relays arranged for operation one at a time to count the impulses, said system having circuits for energizing a diiferent one of the alternate relays of the chain each time the transmitter relay is picked up and for energizing only the next succeeding relay of the chain each time the transmitter relay releases, and also having a circuit for repeatedly energizing said transmitter relay including back contacts of the alternate relays of the chain in series; a repeating relay having a regulated release period, an energizing circuit for the repeating relay including a front contact of the transmitter relay, and means in the circuit for said transmitter relay for regulating the intervals between the successive energizations thereof comprising a back contact of the repeating relay bridged by a front contact of the transmitter relay.

2. In a remote control system provided with a transmitter relay for supplying impulses of selected lengths to a line circuit and having a chain of counting relays arranged for operation one at a time to count the impulses, said system having circuits for energizing a difierent one of the alternate relays of the chain each time the transmitter relay is picked up and for energizing only the next succeeding relay of the chain each time the transmitter relay releases; a repeating relay, an energizing circuit for the repeating relay including a front contact of the transmitter relay, a circuit for repeatedly energizing the transmitter relay including back contacts of the alternate relays of the chain in series, two time controlled contacts each arranged to open in response to a pause in the operation of said transmitter relay, a stick circuit for said transmitter relay including its own front contact and one time controlled contact and arranged to be supplied with current over a front contact of any of said alternate counting relays, a stick circuit for said repeating relay including its own front contact and the other time controlled contact and arranged to 'be supplied with current over a front contact of any of the intervening relays of said chain, and means for connecting a source of current selectively to the front contacts of said counting relays to prolong selected ones of the impulses and intervals supplied to said line circuit.

3. In a remote control system provided with a transmitter relay for supplying impulses to a line circuit and having a chain of counting relays arranged for operation one at a time to count the impulses, said system having circuits for energizing a difierent one of the alternate relays of the chain each time the transmitter relay is picked up and for energizing a different one of the intervening relays of the chain each time the transmitter relay releases, a repeating relay, an energizing circuit for the repeating relay including a front contact of the transmitter relay, a circuit for repeatedly energizing the transmitter relay including back contacts of the alternate relays of the chain in series, a time controlled contact arranged to open in response to a pause in the transmission of said impulses, a stick circuit for said repeater relay including its own front contact and said time controlled contact and arranged to be supplied with current over a front contact of any of the intervening relaysof said chain, and means for connecting a source of current selectively to the front con tacts of said intervening relays to hold said transmitter relay released by said repeating relay, thereby interposing pauses between selected ones of said impulses.

4. In a remote control system provided with a line relay having normal and reverse contacts and responsive to codes of impulses anda transmitter relay for generating such codes together with a series of slow release timing relays for governing the operation of the transmitter relay, circuits controlled by the line relay for energizing said timing relays including circuits for initially energizing two of the timing relays in response to the closing of the reverse contact of the line relay and for successively energizing the remaining timing relays of the series when said two relays are picked up, a stick relay having a pick-up circuit including a front contact of the last timing relay of the series and a stick circuit including a front contact of one of said two timing relays, means controlled by said stick relay when picked up for transferring the circuit for the other of said two timing relays to the normal contact of said line relay, whereby said two timing relays are energized alternately and the remaining timing relays are held energized only in response to the periodic operation of said line 1'5 relay, and means controlled by said timing relays for interposing pauses in the operation ofsaid transmitter relay to characterize the codes generated thereby.

5. In a remote control system having a line relay responsive to codes of impulses and a transmitter relay for generating such codes, a series of three slow release timing relays, a stick relay, a circuit for the first timing relay including a reverse contact of the line relay, two circuits for the second timing relay, one including said reverse contact of the line relay and a back contact of the stick relay and the other including a normal contact of the line relay and a front contact of the stick relay, a circuit for the third timing relay including front contacts of said first and second timing relays in series, a pick-up circuit for said stick relay including a contact closed in response to the energization of said third timing relay and opened a predetermined time after such relay is deenergized, a stick circuit for said stick relayv controlled by a front contact of the first timing relay, and a starting circuit for initiating the operation of the transmitter relay including back contacts of the first and second timing relays in series.

6. In a remote control system provided with a transmitter relay for supplying impulses to a line circuit and a line relay controlled thereby, and also having a chain of counting relays for countin the impulses, and a series of three slow release timing relays; a stick relay having a pick-up circuit controlled by the third timing relay and a stick circuit controlled by the first timing relay of the series, a pick-up circuit for the first counting relay including back contacts of the third timing relay and of the stick relay, a pick-up circuit for each counting relay except the first including front contacts of the next preceding counting relay and of the third timing relay, a stick circuit for each counting relay including a front contact of the third timing relay, the pick-up and stick circuits for the alternate relays of the chain being controlled by a reverse contact, and those of the intervening relays of the chain by a normal contact of the line relay, a circuit for the first timing relay including a reverse contact of the line relay, a circuit for the second timing relay including a normal contact of the line relay, a circuit for the third timing relay closed in response to the energization of the first and second timin relays, and means controlled by said timing and counting relays for governing the operation of said transmitter relay.

7. In a remote control system provided with a transmitter relay for supplying codes of impulses to a line circuit and having a chain of counting relays arranged for operation one at a time to count the impulses, a plurality of panels each containing a first and a second control lever for governing different movable devices in accordance with the character Of different groups of impulses in the codes, a starting relay and an auxiliary relay for each panel, starting means rendered effective when any starting relay is actuated for initiating the operation of said transmitter relay to supply a predetermined number of impulses to the line circuit including a first group of impulses having a code character which identifies a particular panel having its starting relay actuated followed by a second group of impulses of which the code character identifies the position of the first control lever only of such panel, a separate manually operable contact device for each control lever for actuable contact device for the second control lever of any panel for actuating the auxiliary relay for 1 its panel along with the starting relay, and

means rendered effective when such auxiliary relay is actuated for controlling the counting relays to extend the code initiated by such starting relay to include additional impulses comprising a third group of which the code character is determined by the position of the second control lever of such panel.

8. In a remote control system provided with a transmitter relay for supplying codes of impulses to a line circuit and having a chain of counting relays arranged for operation one at a time to count the impulses, a plurality of panels each containing a first and a second control lever for governing difierent movable devices in accordance with the character of different groups of impulses in the codes, a starting relay, an auxiliary relay and a stick relay for each panel, a circuit network for controlling said stick relays by said auxiliary relays in accordance with the positions of said levers and of indication relays controlled by the movable devices which such levers govern, starting means rendered effective when any starting relay is actuated for initiating the operation of said transmitter relay to supply a predetermined number of impulses to the line circuit including a first group of impulses having a code character which identifies a particular panel followed by a second group of impulses of a character determined by the position of the first control lever only of such panel, a separate manually operable contact device for each control lever for actuating the starting relay for its panel, means responsive to the operation of the manually operable contact device for the second control lever of any panel for actuating the auxiliary relay for its panel alon with the starting relay, means rendered eifective when such auxiliary relay is actuated to extend the code initiated by such starting relay to include additional impulses comprising a third group of a character determined by the second control lever for such panel and also by the stick relay for such panel if such relay is energized, and means responsive to a code including said additional impulses transmitted when such stick relay is energized for maintaining it energized until the indication relay for the movable device governed by the second control lever associated therewith is actuated by such device.

9. In a remote control system provided with a transmitter relay for supplying codes of impulses to a line'circuit, and having a plurality of panels containing control levers for governing the operation of movable devices by the codes, a starting relay for each panel, a master relay for initiating the operation of said transmitter relay, manually operable means for energizin said starting relays, means efiective when any starting relay is actuated for energizing said master relay to efiect the transmission of impulses by said transmitter relay including a first group of impulses having a code character which identifies the actuated starting relay followed by a second group of impulses of which the code character identifies the positions of the levers of the corresponding panel, said system being so arranged that when a plurality of starting relays are actuated their codes are transmitted in a fixed order, means for releasing each starting relay as soon as the first group of impulses in .its codes is transmitted, a

recall relay, a recall push button, a stick relay having a pick-up circuit controlled by said push button and a. stick circuit for holding it energized so long as any starting relay is actuated, means for energizing the recall relay when the master relay and said stick relay are both energized, and means for terminating each code transmitted when said recall relay is energized as soon as the first group of impulses in such code is transmitted.

10. In a remote control system of the type described in claim 9, having a plurality of starting relays, a recall relay and push button, and a stick relay which becomes energized when said recall button is operated and is held energized so long as any of said starting relays is energized, an indicator lamp associated with said button, and means for lighting said lamp to cause the display of one distinctive indication when any starting relay is energized and said stick relay is re- 20 leased and to display another distinctive indication when said stick relay is energized.

11. In a remote control system provided with a line relay responsive to codes of impulses received such devices, a starting relay and a code indicator relay for each panel, manually operable means for energizing said starting relays, means efiective when any of said starting relays is actuated for initiating the operation of said transmitter relay to effect the transmission of a group of impulses of a code character identifying the actuated starting relay, means for releasing such starting relay as soon as such group of impulses is transmitted, means controlled by the actuated starting relay for energizing the associated code indicator relay, means for maintaining said code indicator relay energized until the indication relays of the corresponding panel are actuated in response to a received code, a code indicator lamp, and means for lighting said lamp to display one distinctive indication when the starting relay and the code indicator relay are both energized and to display anoth'er indication when only said code indicator relay is energized.

ARTHUR P. JACKEL.

REFERENCES CITED The following references are of record in the from a line circuit and controlling a transmitter 25 file of t patent;

relay for supplying such codes to the line circuit, a plurality of panels containing control levers for governing the operation of movable devices by such codes, and indication relays responsive to received codes for indicating the condition of 30 2,215,407

UNITED STATES PATENTS Number Name Date 2,126,210 Preston Aug. 9, 1938 Phinney Sept. 17, 1940 

